Design Related Advantages for adapting Precast Framing System for the Superstructure

Er. Kapilesh Bhate, Precast India Infrastructures Pvt.Ltd

Precast India Infrastructures

In the wake of some technical revisions in the IS codes, following codes are mandatory to be followed
  • IS 1893 (2016)
  • IS 13920 (2016)
The total and exact effects of these changes is a subject of long discussions and probably, some debate due to interpretation differences, however, to summarise in short, for the benefit of the esteemed readers, following are the implied restrictions laid by the code on Flat Slab Post Tensioned structures, which used to be the most common system of construction, especially for commercial large span structures:
  1. Flat Slab system cannot be considered as a part of earthquake (lateral load) resisting system, i.e. the columns shall not be allowed to contribute to resisting any earthquake forces, and should avoid punching failure anyway
  2. The shear walls should be provided with ductile detailing to resist 100% of design earthquake forces
  3. 25% of the design earthquake forces to be resisted by peripheral moment resisting frame
  4. The Flat Slab system structures henceforth, will have to be designed with R=3 and not R=5, i.e. the earthquake forces shall increase on the current structure by 66%
  5. Importance Factor for the buildings shall be 1.2 minimum as opposed to 1, in the previous code (this is mostly for all structures though, not only flat slab)
  6. The top storey drift shall be restricted to 0.1%, which is a new and a very stringent constraint laid by the code, which will lead to increase in shear walls in following aspects:
    1. Locations
    2. Length
    3. Thickness
    4. Reinforcement Steel
    5. As per experience of numerous design experts, and outcomes of various technical seminars, it is believed that just the shear walls in the core area may not be sufficient to fit in these stringent criteria and we may require shear walls in other, more evenly spread out locations, to increase the stiffness of the building, which may bring obstructions in the clear floor plates of the IT office spaces, which may go against the very basis of selection of PT Flat Slabs for ‘flexible’ IT Office Spaces (Or introduction of grid beams, usually wider in nature – upto 2 to 2.5m wide and 400 to 500 deep, to act as a frame to transfer the lateral forces to the shear walls as efficiently as possible)
  7. All shear walls must start from footing levels right till the top of the building (terrace), so, the shear walls mentioned in point 6 may obstruct parking drive ways in the lower floors (parking) as well
  8. Above mentioned points are only a few important changes from the old to the new code, applicable to the CIS PT Flat Slab structure (our current structure type)
  9. These clauses clearly can be translated to the following challenges
    1. increase in concrete
    2. increase in steel/ strands
    3. increase in challenges to frame the structure and pass in design critrea
    4. increase in shear wall locations, inconveniencing Office and Parking Floors
  10. To summarise, increase in cost and work, hence adds cost and time
Precast India Infrastructures

Design Related Advantages of Precast Framing Plan
  1. Given the above heavy restrictions on the PT Flat Slab, an efficient solution opens out as a Frame Structure with Shear Wall System, and since in Precast System, we shall be providing emulative monolithic ductile moment resisting connections, we can provide for the above mentioned challenges, especially in case of
    1. Long Spans
    2. Creation of columnless Spaces
    3. Lower beam depths than conventional CIS frames
    4. Heavy loadings
  2. Of the above mentioned clauses, only the Importance Factor Clause shall be applicable to the Precast System, so our earthquake systems will not double like in Flat Slab PT System, but only increase 1.2 times.
  3. These increased forces can be tried best to be contained in the existing sizes and lengths of shear walls, as per architect’s requirement, due to the contribution of the moment resisting frames of the columns.
Precast India Infrastructures

Other Non-Design Related Clear Advantages of Precast System
  1. Quality of construction
  2. Speed of construction
  3. Less labour on site
  4. Safe Working Procedures
  5. Due to increase in quantities and cost of CIS PT Options due to the above mentioned factors, cost would almost not be a deciding factor any more
  6. Due to elimination of excise, duty, and application of GST for both, conventional and Precast system, the cost comparison also remains apple to apple now
  7. Less Noise
  8. Less Dust
  9. Pre-Engineering possible in the period upto hitting ground hence client budget can be frozen early enough
  10. Advance Production of Typical elements to win race against time
  11. Parallel progress of serially dependent different activities, not possible in CIS
  12. 3D BIM for systematic design, planning providing coordinated results.

NBM&CW January 2018

Click Here
To Know More / Contact The Manufacturer
Please provide your details we will contact you as soon as possible
Please let us know your name.
Invalid Input
Please let us know your Designation.
Invalid Input
Please let us know your City.
Please let us know your State.
Please let us know your Country.
Please let us know your Contact Number.
Please let us know your email address.
Please brief your query.

Noise control in Western Australia: BGC precast invests in battery mould for concrete precast-walls

BGC Precast, belonging to BGC Group and based in Kwinana, Western Australia, has invested in a battery mould from Tecnocom, Italy, a company belonging to the PROGRESS GROUP, which is one of the leading groups in ma- chinery and solutions Read More ...

Precast Concrete Construction Technologies for Metro Projects in India

The most dramatic development in the field of urban infrastructure in recent times has undoubtedly been the introduction of the metro as a public transportation system. Apart from providing the predominant mode of travel, the metro has been Read More ...

Elematic: In the Forefront with Innovative Solutions

Leading precast technology supplier Elematic has introduced a new automatic Modifier E9 for hollow-core slab production and a WallMES system for the optimization of precast wall panel production which covers automatic production Read More ...

Precast Pavement Perfection

Time after time, precast concrete has been proven the material of choice when replacing our nation's roadways. Offering strength, durability, fast installation times and a controlled manufacturing environment, precast was Read More ...

A Sight to See - Precast concrete enhances the beauty of the Academy Museum of Motion Pictures

It will soon be one of the most eye-catching structures in the country. The 300,000-square-foot Academy Museum of Motion Pictures, dedicated to the art and science of the film industry, will open in late 2019 in Los Angeles Read More ...

New Elematic Extruder E9

Elematic introduces an all-new flagship model 'the Extruder E9' to their Extruder family for hollow-core slab production. The new machine will offer high casting speed, 2nd generation automatic compaction control and sophisticated Read More ...

Precast Technology Enabling High-rise Construction at Lower Cost

Precast technology has many advantages such as speed, quality and cost over the traditional construction method - the reason why it is particularly suited for high-rise projects, says Petteri Laitinen, Vice President, Projects and Read More ...

Infrastructure Project in Kuwait – Tecnocom moulds form bridge girders at Nawaseeb Road

Infrastructural projects in Kuwait are still the focus of local government-backed investments. In order to improve connectivity, regional and global projects in the infra sector are viewed as a state priority Read More ...

Creating Space with Prefab

The Museum hosts examples of Baroque art ranging from painting, sculpture and fashion to architecture, music, theatre, literature and food. Fluted slabs white concrete with a bush-hammered finish forms the walls, while maintaining Read More ...

Indonesian Property Developer Sets New Construction Standards – New Precast Plant From EBAWE

With more than 1,600 ha. of real property and development potential for the next 12 years, PT Modernland Tbk. is one of the leading Indonesian property developers in Greater Jakarta. For the last three decades, the Read More ...

The 3D Monolithic Volumetric Precast

The construction industry is buoyed by predicted growth and expansion, however, it continues to underperform in four strategic areas: Productivity, Certainty in Delivery, Skills Shortage, and Data Transparency. Poor Read More ...

Elevated Corridors For - Metro & Road Connectivity

India has taken a giant leap in the field of construction over the past 15-20 years. And infrastructure development is feather to the cap. A large number of cities are constructing metro projects. Similarly, an average of Read More ...

Earthquake-Proof Construction

The Pacific Ring of Fire is a volcanic belt which rings the Pacific Ocean on three sides with a length of over 40,000 km. The friction of the tectonic plates makes this region a zone of frequent earthquakes, which, in Read More ...

German's latest Precast Concrete Technology in Indonesia

PT Modernland Realty Tbk, through its subsidiary PT Modern Panel Indonesia, one of the country’s leading material building producers, continues to develop innovative solutions for the development of the Read More ...

Precast Bridge: Banking on Precast

According to the 2017 Bridge Report by the American Road & Transportation Builders Association, more than 185 million vehicles cross nearly 56,000 structurally deficient bridges every day in the U.S. As such, deteriorating Read More ...

Precast Construction - Elematic Helps B. G. Shirke to Execute Mass Projects

It has been the dream of our founder- chairman, Padmashri B.G. Shirke, to industrialize the civil engineering construction in our country by manufacturing standardized precast components for building Read More ...
NBM&CW

New Building Material & Construction World

New Building Material & Construction World
MGS Architecture

Modern Green Structures & Architecture

Modern Green Structures & Architecture
L&ST

Lifting & Specialized Transport

Lifting & Specialized Transport
II&TW

Indian Infrastructure & Tenders Week

Indian Infrastructure & Tenders Week